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How many significant figures does each of the following numbers have?

a)  310

b)  0.00310

c)  1.031

d)  3.10×10⁵

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Solution:

Part a

Zeroes before the decimal point merely locate the decimal point and are not significant. Thus, 310 has 2 significant figures. 

Part b

Trailing zeros after the decimal point are significant because they indicate increased precision. Therefore, 0.00310 has 3 significant figures. 

Part c

Zeroes between nonzero digits are significant. Therefore, 1.031 has 4 significant figures. 

Part d

Just like in part b, trailing zeros after the decimal point are significant because they indicate increased precision.Therefore, 3.10×10⁵ has 3 significant figures.

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